‘You do not need fibre,’ reads the Simplistic Answers To Common Objections section on /r/zerocarb, a forum populated by self-proclaimed carnivores, where unrepentant vegans are strongly discouraged from posting. ‘Fat is not bad for you. Meat and water. That’s it,’ a post claims. There are 54,000 subscribers to /r/zerocarb, hundreds online at any one time – and they’re just the tip of an iceberg of modern-day carnivores who claim that we, as humans, are better-adapted to eating meat than fibre, in contrary to the advice of thousands of nutritionists and medical professionals.
The rest of the board is filled with questions and commentary, success stories and steak-based selfies. It’s a positive vibe, and it’s difficult to read without thinking that, wait, maybe this meat-only thing really works. But does it? Here’s your simplified guide to a divisive diet…
How does it work?
It varies. Some people eat offal and organs for improved vitamin intake, or fish for a better ratio of omega 3:6 fats, as well as eggs (and sometimes dairy products) and occasionally drink coffee or alcohol. Others eat almost nothing but steak, salt and water and claim to feel fine.
OK but does it actually work?
It depends on what you mean by ‘work’. Carnivores claim that the diet mimics a caveman lifestyle much more than the more popular ‘paleo’ diet – that we ate much more meat than fruit or vegetables because the latter were so inefficient to gather. There are, they point out, examples from tribal peoples existing on mainly-meat diets for their entire lifespans – including the Inuit, who admittedly eat a lot more fish than steak, but also the Masai.
Carbohydrates, carnivores claim, are ruining us: playing havoc with our insulin levels and prompting wild fluctuations in energy throughout the day. Carnivores often link fruit and vegetable intake to inflammation, claiming that defence mechanisms in plants – including lectins, gluten and phytic acid – can cause inflammation in the body.
‘There are examples of tribal peoples existing on mainly-meat diets for their entire lifespans’
And is there evidence?
Not in the scientific sense. Plenty of carnivores report weight loss, but that’s unsurprising: it’s a restrictive diet, and it’s highly unlikely that anyone on it is eating more calories than they were previously, even on three or four steaks a day. They probably also benefit from a spike in testosterone: a study published in the American Journal of Clinical Nutrition found that men who followed a high-fat, low-fibre diet for 10 weeks ended the experiment with a 13% increase in testosterone compared with subjects who kept the fat low and the fibre high.
Muscle will also probably improve: it’s basically impossible to go carnivore without drastically increasing your protein intake to well over the 1.6g per kilo of bodyweight, which a recent review of studies recommend as a prerequisite for muscle (although we wonder if you would have enough energy from zero carbs to train optimally.)
There’s also some evidence to back up claims about inflammation: a 2013 study published in the journal Metabolism, for instance, found that test subjects on a high-fat diet had lower markers of systemic inflammation after 12 weeks than those eating more carbs. But a key problem is that, for obvious reasons, there have been no control-group studies that compare a strict carnivore diet to any other kind. Dr Shawn Baker, who eats almost nothing but steak and holds a handful of indoor rowing records, is organising his own online evidence-collecting effort, but so far it’s mostly anecdotal.
Are they right about fibre and fat?
Well, the fat part is the least contentious: a large-scale review of 21 studies published in 2010 concluded that there was no association between saturated fat consumption and heart disease, and other studies suggest that eating more of it can raise HDL cholesterol – the ‘good’ kind. (That said, a heart surgeon RSNG spoke to recently still recommended limiting saturated fat intake.)
The fibre part is much more divisive: it’s true that it’s an indigestible substance, not necessary for nutrients, but a recent meta-review showed a link between eating fibre and lowered mortality from any cause. (Read more in the RSNG article on this.)
Fibre feeds good gut bacteria, keeping our intestines and immune systems in order, and new science is linking the gut biome to brain functions and even our emotions. Carnivores counter that fibre is only necessary if you’re eating other junk food, but don’t offer scientific evidence. Omnivores point out that the gut thrives on the bacteria it builds up by feeding on fibre – carnivores claim that if all you’re eating is steak, you won’t need it, but again, no studies have been done to test this idea.
What about carnivores who claim other health benefits?
Fat loss aside, the most interesting results come from performance athletes and the seriously ill: New Zealand All Black Owen Franks, for instance, credits the diet with helping him get bigger and leaner, while other members of the carnivore community report relief from a host of serious autoimmune and digestive problems, from Lyme disease and arthritis to anxiety and depression.
Opponents point out that the effects shown so far could be nothing more than placebo. Some carnivores – those who were suffering from severe depression or crippling rheumatoid arthritis before going meat-only in desperation – say that the effects they’ve experienced can’t just be all in the mind. But again, there’s no control-group evidence.
‘More well-researched diets give similar results: cutting down on sugar and processed foods does plenty’
So can I live on meat alone?
Probably: the Masai do it (although they drink milk too), polar explorer Vilhaljmur Stefansson did it for a year of supervised study in a medical facility, and there are people on /r/zerocarb who claim to have done it for decades, although to avoid scurvy and other conditions they’re probably on some vitamin supplementation (Vitamin C is the only essential vitamin not found in useful amounts in cooked meat.)
A better question is whether it offers any benefits that aren’t possible with easier diets, and less risk: and that’s where the answer is a resounding no. If someone was struggling with the effects of chronic disease and nothing else works, it could be worth a short-term try, but it’s desperation stakes (and you should always check with a qualified doctor before going on any kind of diet because your current state health could rule it out).
If all you’re interested in is getting lean or jacked, improving performance or upping your mental energy, there are more well-researched diets that promise similar results: just cutting down on sugar and processed foods will do plenty. And if you want to save shopping or thinking time by eating nothing but steaks be aware that you might be doing more harm than good in the long run. Indeed, the UK Government has previously advised its citizens not to eat more than 500g (1lb) of red meat a week, to limit the risk of bowel cancer. So yes, you can do it: but that doesn’t mean you should.
WHAT NEXT? Visit Shawn Baker’s online home for more of his take on going carnivore, including the way he trains, eats, as well as testimonials from other happy meat eaters.
Comments are for information only and should not replace medical care or recommendations. Please check with your Doctor before embarking on nutrition regimes for the first time.